System for managing configuration changes in a data processing system

ABSTRACT

A method of managing configuration changes in a data processing system, particularly a network wherein software products ( 250 ) must be distributed to client workstations. The method provides the definition of reference models ( 220   e - 220   d ) arranged in a tree ( 215 ); each reference model includes configuration elements (such as software products and/or hardware features and their desired target status) for the corresponding client workstations (subscribers). A target configuration ( 230 ) of the client workstations associated with each reference model is determined by inheriting the configuration elements of the parent reference models. A list of actions ( 245 ) to be carried out on each client workstation for reaching the corresponding target configuration is determined by comparing the target configuration with a current configuration of the client workstation stored in a corresponding inventory ( 245 ).

The present invention relates to a method and system for managingconfiguration changes in a data processing system.

Managing configuration changes in a data processing system is a timeconsuming activity, particularly when the system includes a great numberof destination units on which new configurations must be enforced. Atypical example is that of a large network with hundreds of workstationswhere software products and/or hardware features are periodicallyupgraded in order to be abreast of the information technologydevelopment.

Software distribution applications have been proposed in the last yearsto assist a system administrator in efficiently managing deployment ofsoftware products to (client) workstations. A software distributionapplication runs on a server workstation and controls building ofpackages including new software products (or new versions thereof) to beinstalled and instructions understandable by the client workstations.Each package is distributed to the respective client workstation throughthe network; the instructions embedded in the package cause the softwareproducts to be automatically installed or removed in order to reach thedesired (software) configuration of the client workstation.

However, this solution is not completely satisfactory. Particularly, theadministrator is faced with the burden of manually defining the packagesto be distributed to the client workstations. Moreover, theadministrator cannot rely on information provided by the softwaredistribution application for deciding which software products must beinstalled and/or removed and on which client workstations the newconfigurations must be enforced. As a consequence, the process ofmanaging the configuration changes is very complex and error-prone.

The drawbacks of the solutions known in the art are particularly acutein large systems, where different and frequent configuration changes areenforced on various destination units.

It is an object of the present invention to overcome the above-mentioneddrawbacks. In order to achieve this object, a method as set out in thefirst claim is proposed.

Briefly, the present invention provides a method of managingconfiguration changes in a data processing system having a plurality ofdestination units, the method including the steps of providing aplurality of reference models arranged in a tree starting from a rootreference model, associating each destination unit with a referencemodel including configuration information specific for the correspondingdestination units, determining a target configuration for thedestination units associated with a selected reference model accordingto the configuration information of the reference models in a path fromthe root reference model to the selected reference model, and causingeach destination unit associated with the selected reference model to beupdated according to the target configuration.

Moreover, the present invention also provides a computer program forperforming the method, a product storing the program, and acorresponding data processing system.

Further features and the advantages of the solution according to thepresent invention will be made clear by the following description of apreferred embodiment thereof, given purely by way of a non-restrictiveindication, with reference to the attached figures, wherein:

FIG. 1 is a basic block diagram of a networking system in which themethod of the invention can be used;

FIG. 2 shows a partial content of a working memory of a serverworkstation included in the networking system;

FIG. 3 a-3 b are a flow chart of a method for managing configurationchanges to client workstations of the networking system.

With reference in particular to FIG. 1, there is shown a networkingsystem 100, such as a WAN (Wide Area Network) used in a large company.The networking system 100 if formed by a plurality of workstations 105,typically consisting of PCs (Personal Computers). The workstations 105are clustered around corresponding concentrators 110 (such asrouters/hubs); the concentrators 110 are installed at distributed sitesand are connectable by a telephone line 115. The networking system 100has a client/server architecture, wherein one or more of theworkstations 105 (generally consisting of powerful computers) managenetwork resources, such as shared files and devises; the otherworkstations 105 operate as clients on which end-users run applicationsrelying on server resources.

Each workstation 105 includes several units, which are connected inparallel to a communication bus 120. In particular, a central processingunit (CPU) 125 controls operation of the workstation 105, a workingmemory 130 (typically a DRAM) is used directly by the CPU 125, and aread-only memory (ROM) 135 stores a basic program for starting theworkstation 105. Various peripheral units are further connected to thebus 120 (by means of respective interfaces). Particularly, a bulk memoryconsists of a hard-disk 140 and of a driver unit (DRV) 145 for readingCD-ROMs 150; the workstation 105 further includes an input unit (IN)155, which consists for example of a keyboard and a mouse, and an outputunit (OUT) 160, which consists for example of a monitor. A networkinterface card (NIC) 165 is used to connect the workstation 105 to theconcentrator 110.

Similar considerations apply if the networking system is associated witha department of the company (or with any other entity), if thenetworking system has a different topology, if the networking systemconsists of a LAN (Local Area Network), if the networking systemincludes different components (such as one or more switches), if eachworkstation has a different structure (for example with amulti-processor architecture), and the like.

Considering now FIG. 2, there is shown a partial content of the workingmemory 130 of a workstation operating as a software distribution server;the information (programs and data) is typically stored on the hard-diskand loaded (at least partially) into the working memory 130 when theprograms are running, together with an operating system and otherapplication programs (not shown in the figure). The programs areinitially installed onto the hard disk of the server workstation fromCD-ROM.

The working memory 130 includes an input/output interface (I/O) 205 forexchanging information with the peripheral units of the serverworkstation. The input/output interface 205 communicates with a changeconfiguration management module (CONFIG) 210.

The configuration module 210 controls a repository (MODELS) 215 ofreference models, each one defining a profile with configurationinformation specific for the corresponding client workstations. In theexample at issue, the repository 215 includes an enterprise model 220 e,a secretary model 220 s, a manager model 220 m and a developer model 220d. The configuration module 215 further accesses a company database 225.

A generic reference model includes one or more records definingrespective configuration elements. Each record consists of a field ELEidentifying the configuration element, such as a software product or ahardware feature. A field TGT denotes a desired target status of theconfiguration element; for example, the target status for a softwareproduct indicates that the software product is to be installed, removed,or installed/removed in an undoable manner, while the target status fora hardware feature indicates a hard-disk size, a CPU model, or a workingmemory capacity. A further field DPD includes dependency informationindicating logic relations between the configuration elements; forexample, the filed DPD contains the configuration elements required forrunning a software product (pre-requisites), the configuration elementsin conflict with the software product (ex-requisites), or theconfiguration elements to be installed in a certain order together withthe software product (co-requisites).

The reference model further includes a field SBS, which is used toassociate the reference model with one or more client workstations(subscribers); the association is carried out statically and/ordynamically. When the subscribers are defined statically, the field SBSsimply contains a list of the client workstations; conversely, when thesubscribers are defined dynamically, the field SBS contains a query tobe run on the company data base 225, whose result provides the list ofthe client workstations.

The reference models are hierarchically arranged in a tree.Particularly, the enterprise model 220 e defines a root of the tree; thesecretary model 220 s and the manager model 220 m depend on theenterprise model 220 e, and in turn the developer model 230 d depends onthe manager model 220 m. As described in detail in the following, eachchild reference model 220 s, 220 m and 220 d (which depends on acorresponding parent reference model 220 e, 220 e and 220 m,respectively) inherits the configuration information of all thereference models in a path from the root reference model 220 e to thechild reference model. It should be noted that the inheritance mechanismdoes not implement an “is-a” semantic; for example, a developer is not amanager, but all the configuration elements (not the subscribers)belonging to the manager model 220 m are inherited by the developermodel 220 d.

The company database 225 defines an organisation chart of the companyand consists of a relational table formed by a record for each employee.The record is composed of a field INFO containing information about theemployee, such as his or her name, telephone and facsimile numbers,e-mail address, department, position, manager and subordinate persons(if any), and the like. A field WS identifies the client workstationassigned to the employee, for example its type, serial number, location,and IP address. A flag EX indicates that the client workstation assignedto the employee is to be excluded from the result of the query (whenasserted).

The configuration module 210 generates a memory structure 230 indicatinga target configuration for the client workstations associated with aselected reference model. The target configuration 230 includes one ormore configuration elements, each one defined by the respective fieldsELE and TGT (indicating the configuration element and its target status,respectively), and the list of the client workstations associated withthe selected reference model, each one identified by the respectivefield WS.

The target configuration 230 is supplied to a synchronisation engine(SYNC) 235, which accesses an inventory 240 storing a currentconfiguration of the client workstations. The configuration inventory240 includes a record for each client workstation; the record consistsof the respective field WS (identifying the client workstation) and afield CURR denoting the hardware features of the client workstation andthe software products installed thereon. The synchronisation engine 235further accesses a state transition table 243. The state transitiontable 243 consists of a lookup table, wherein each record has a keyformed by a field STSs and a field STSe; the fields STSs and STSeindicate a starting status and an ending status, respectively, of ageneric configuration element belonging to a corresponding category(such as hardware feature or software product). The key STSs,STSe isassociated with an attribute consisting of a field ACT indicating anaction to be performed for reaching the ending status STSe from thestarting status STSs (for example installing a software product,removing a software product, upgrading the CPU, increasing the size ofthe hard-disk, and so on).

The synchronisation engine 235 generates a memory structure 245 defininga list of actions to be performed on each client workstation associatedwith the selected reference model for reaching the target configuration.Particularly, the action list 245 includes a series of records, each oneconsisting of the field WS identifying the client workstation, the fieldELE identifying the configuration element involved, and the field ACTindicating the corresponding action to be carried out on the clientworkstation.

The action list 245 is provided to a deployment agent (DEPL) 250, whichaccesses a repository (SW) 255 of the software products. The deploymentagent 250 builds a distribution package (PCK) 260 for each clientworkstation; the distribution package 260 consists of one or more filescontaining the software products to be installed on the clientworkstation and instructions for automatically executing the actions(relating to software products) indicated in the corresponding recordsof the action list 245 (such as installing the software productsincluded in the package or removing other software products). Thedeployment agent 250 further controls the updating of information storedin the configuration inventory 240.

The distribution packages 260 are provided to a network interface (NET)265, which sends the packages to the corresponding client workstationsaccording to a plan scheduled by the deployment agent 250. The networkinterface 265 is also connected to the deployment agent 250 directly forsupplying messages received from the client workstations. Thesynchronisation engine 235 and the deployment agent 250 furthercommunicate with the configuration module 210 for receiving commands andproviding return codes indicative of a result of the correspondingoperations.

Similar considerations apply if the programs and data are structured ina different manner, if other modules or functions are provided, if thetree consists of a different number of reference models, if one or moreof the reference models are dummy models without any subscriberassociated therewith, if the company database has a differentarchitecture and stores other information, if two or more clientworkstations are assigned to some employees, and the like.Alternatively, equivalent configuration information is included in thereference models, different configuration elements are managed (such asapplication parameters, databases, audio and video recordings, or anyother digitally encoded product), different target status are supported(for example indicating that a software product must be simply disabledbut not removed), or the subscribers consist of different destinationunits (such as software applications or profiles associated withrespective users logging into the client workstations).

As shown in FIG. 3 a-3 b, a whole software distribution applicationconsisting of the configuration module, the synchronisation engine andthe deployment agent performs a method 300 when running on the serverworkstation. The method 300 starts at block 303 and then passes to block306, wherein a menu with a series of possible choices is displayed to asystem administrator on the monitor of the server workstation. Themethod executes the operations corresponding to the choice selected bythe administrator. Particularly, if the administrator has selected thefunction of editing the reference model repository the blocks 309-318are carried out, while if the administrator has selected the function ofdeploying a new configuration to the corresponding client workstationsthe blocks 320-375 are carried out; conversely, if the administrator haschosen to exit the software distribution application, the method ends atthe final block 378.

Considering now block 309 (editing function), the administrator deletesa selected reference model (restructuring the tree accordingly), insertsa new reference model into the tree, or selects a reference model to beupdated. The method continues to block 312, wherein if a reference modelhas been selected for updating the administrator deletes a configurationelement, creates a new configuration element, or updates the targetstatus of a selected configuration element. Passing to block 315, theadministrator edits the dependency information for the selectedconfiguration element (pre-requisites, ex-requisites or co-requisites),for example adding, updating or deleting items. With reference to block318, the administrator modifies the subscribers assigned to the selectedreference model; particularly, the identifier of a client workstation isdeleted from the corresponding list, the identifier of a new clientworkstation is inserted, or the query dynamically defining the list ofthe client workstations is created or updated. The method then returnsto block 306 waiting for a new command by the administrator.

Considering now block 320 (deployment function), the administratorselects one of the reference models to be enforced. The method descendsinto block 321, wherein all the configuration elements of the rootreference model are added to the target configuration (empty at thebeginning). The configuration module than checks at block 324 whetherthe selected reference model has been reached (and completelyprocessed). If so, the method passes to block 325 (described in thefollowing). On the contrary, the method proceeds to block 330, wherein anew configuration element of the reference models down the tree along apath from the root reference model to the selected reference model isconsidered (staring from the first configuration element in the childreference model depending from the root reference model directly). Ifthe target configuration does not include the current configurationelement, the method continues to block 333, wherein the currentconfiguration element is added to the target configuration; conversely,the method continues to block 336, wherein the target status and thedependency information of the (previous) configuration element in thetarget configuration are replaced with the corresponding fields of thecurrent configuration element. In both cases, the method returns toblock 324 for processing a next configuration element of the samereference model or the first configuration element of a next referencemodel.

Considering now block 325, the target configuration is updated accordingto the corresponding dependency information, in order to resolve all thelogic relations between the configuration elements. For example,configuration elements corresponding to the pre-requisite products andthe co-requisite products to be installed are added, the configurationelements are rearranged for meeting the required order of installation,or configuration elements corresponding to the ex-requisite products tobe removed are inserted.

The method then passes to block 338, wherein the configuration moduleverifies whether the subscribers are defined statically or dynamicallyin the selected reference model. In the first case, the list of theclient workstations included in the selected reference model is added tothe target configuration at block 339, and the method then descends intoblock 342 (described in the following). Conversely, if the subscribersare defined dynamically the corresponding query included in the selectedreference model is run on the company database at block 345 in order toextract the list of the client workstations. The list is pruned at block348 of the client workstations to be excluded from the deployment of thenew configuration according to the corresponding flag. The method thenpasses to block 342.

Considering now block 342, the current configuration of the clientworkstations associated with the selected reference model is extractedfrom the configuration inventory. The synchronisation engine thengenerates at block 351 the action list for each client workstation bycomparing the target configuration with the corresponding currentconfiguration. Particularly, if the current status of each configurationelement (software product or hardware feature) meets the desired targetstatus, no action is performed; conversely, the action required to reachthe target status of the configuration element from its current statusis extracted from the state transition table and added to the list.

The method proceeds to block 354, wherein the deployment agent verifieswhether a current hardware structure of the client workstationsassociated with the selected reference model meets the hardwarepre-requisites of the target configuration. For all the clientworkstations that meet the hardware pre-requisites of the targetconfiguration, the corresponding distribution package is built at block357; more specifically, the deployment agent inserts each softwareproduct to be installed into the distribution package, and addinstructions for performing the required actions. Conversely, for allthe client workstations that do not meet the hardware pre-requisites ofthe target configuration, for example because the CPU model cannot runthe software products to be installed or the hard-disk size isinsufficient, an error condition is entered at block 366; particularly,a warning is provided to the administrator and the deployment of thetarget configuration to these client workstations is aborted.

In both cases, the method continues to block 372, wherein the packages(if any) are sent to the respective client workstations through thenetwork. Each package is received on the client workstation; theinstructions embedded in the package are executed in order to install orremove the corresponding software products. A return code message issent back from each client workstation to the server workstation forreporting the result of the configuration change; the deployment agentupdates the configuration inventory accordingly at block 375. The methodthen returns to block 306 waiting for a new command by theadministrator.

The following tables define an example of configuration elementsbelonging to each reference model:

Field ELE Field TGT Enterprise model E-mail program (software program)Installed Anti-virus (software program) Installed Working memory size(hardware feature) >=64 MB Secretary model Office automation (softwareprogram) Installed Games (software program) Not installed Manager modelOffice automation (software program) Installed Reporting (softwareprogram) Installed Developer model Compiler (software program) InstalledReporting (software program) Inst. undoable Working memory size(hardware feature) >=128 MBLet us suppose now that we want to enforce the developer model. Thetarget configuration for the client workstations associated with thedeveloper model is defined as:

Field ELE Field TGT E-mail program (software program) InstalledAnti-virus (software program) Installed Working memory size (hardwarefeature) >=128 MB Office automation (software program) InstalledReporting (software program) Inst. undoable Compiler (software program)InstalledAs a consequence, if a client workstation associated with the developermodel has only the anti-virus installed thereon and its working memorysize is greater than 128 MB, the following list of actions is to beperformed for reaching the target configuration:

Field ELE Field ACT E-mail program (software program) Install Officeautomation (software program) Install Reporting (software program)Install, undoable Compiler (software program) Install

Likewise considerations apply if an equivalent method is performed, forexample if report functions are provided, if the company inventory isstored elsewhere and the query is run by another workstation, and so on.

More generally, the present invention provides a method of managingconfiguration changes in a data processing system having a plurality ofdestination units. The method includes the steps of providing aplurality of reference models arranged in a tree starting from a rootreference model, and associating each destination unit with a referencemodel including configuration information specific for the correspondingdestination units; the method further includes the steps of determininga target configuration for the destination units associated with aselected reference model according to the configuration information ofthe reference models in a path from the root reference model to theselected reference model, and causing each destination unit associatedwith the selected reference model to be updated according to the targetconfiguration.

The devised solution provides a scalable and flexible way of specifyingthe target configuration of each destination unit. Particularly, thereference models allow the destination units to be arranged intological, functional groups according to the role that each destinationunit plays in the system. Therefore, any profile or organisationalchange can be automatically reflected on the destination units involvedsimply modifying the corresponding reference models. In this way, alarge system with a great number of destination units can be managed asa small system, by handling all the destination units associated witheach reference model as a single entity.

The hierarchical structure of the reference models greatly simplifiesthe modelling of the destination units, by allowing a step-by-stepdefinition of the target configuration of each destination unit; infact, the configuration elements common to all the destination units aredefined only in the root reference model, and the configuration elementsspecific for each functional group are defined moving down the tree. Inthis way, the number of reference models needed to describe the wholesystem is greatly reduced; moreover, each change to a reference model isautomatically reflected into the target configuration of all thedestination units associated with its child reference models.

The solution according to the present invention simplifies thedeployment of new configurations in the system. As a consequence, theprocess of managing frequent configuration changes to different groupsof destination units is made more reliable.

The preferred embodiment of the invention described above offers furtheradvantages. For example, the algorithm proposed for determining thetarget configuration from the corresponding reference models along thepath from the root reference model to the selected reference model isparticular simple and effective. This solution allows any referencemodel to inherit all the configuration elements of the parent referencemodels; at the same time, each reference model can override the targetstatus or block the installation/removal of any configuration elementdefined in the parent reference models.

Alternatively, the target configuration is determined in a differentmanner, for example without the possibility of overriding and/orblocking the configuration elements defined in the parent referencemodels.

The dependency information inserted in the reference models preventsdefinition and enforcement of incorrect configurations. In addition, theverification of the current hardware structure of each destination unit(in order to check whether it meets the hardware pre-requisites of thetarget configuration) ensures that each destination unit is at a levelallowing all the software products to be installed to run correctly.

Likewise considerations apply if the dependency information is used in adifferent manner for determining the target configuration, if the methodonly verifies compliance of the target configuration with thecorresponding dependency information (without modifying the targetconfiguration but simply entering an error condition if the result ofthe verification is negative), if the dependency information is notdefined in the reference models but in a distinct memory structure thatis accessed by the configuration module each time a reference model mustbe enforced, if the package is sent to the client workstations in anycase (even if an error condition has been entered), and so on. However,the solution according to the present invention leads itself to becarried out even without the possibility of defining any dependencyinformation for the configuration elements or any hardware feature inthe reference models.

The dynamic definition of the subscribers associated with each referencemodel makes it possible to evaluate the destination units to which theconfiguration changes must be enforced when the new configuration isactually deployed. Moreover, the possibility of excluding somedestination unit from the result of the query allows these destinationunits to be left temporary unchanged without modifying the fielddefining the subscribers in the corresponding reference model.

Alternatively, the destination units are associated with each referencemodel in a different manner, for example defining groups of destinationunits (such as the client workstations attached to a specified router),the whole result of the query is always employed (without thepossibility of excluding any destination unit), the subscribers aredefined only statically or dynamically, and the like.

The inventory storing the current configuration of each destination unitallows a level of the configuration elements present on the clientworkstations to be efficiently tracked. For example, the administratorcan easily decide where to distribute a new software product alreadyinstalled on a subset of the client workstations and now to be installedon all the client workstations of the system, or where to distribute anew version of a software product already installed on a subset of theclient workstations.

The method described above is particularly advantageous for a softwaredistribution application used in a large network, wherein the newconfigurations are automatically deployed from the server workstation toa great number of client workstations.

Similar considerations apply if the state transition table is replacedby an equivalent memory structure, or if the list of actions isdetermined in a different manner according to a comparison between thetarget configuration and the current configuration of each destinationunit (for example with an algorithm embedded in the synchronisationengine). However, the proposed solution leads itself to be implementedeven without any configuration inventory (for example collecting theinformation indicative of the current configuration of each clientworkstation dynamically by the server workstation); moreover, the methodof the invention is also suitable to be used in a different dataprocessing system (even with the destination units not connected to eachother in a network, for example copying the packages onto CD-ROMs thatare manually distributed), or for controlling only hardwareconfigurations.

Advantageously, the method proposed by the present invention isimplemented with a computer program, which is provided on CD-ROM.

Alternatively, the program is provided on floppy-disk, is pre-loadedonto the hard-disk, or is stored on any other computer readable medium,is sent to the computer through the network, is broadcast, or moregenerally is provided in any other form directly loadable into a workingmemory of a computer. However, the method according to the presentinvention leads itself to be carried out even with a hardware structureinstalled on the server workstation, for example integrated in a chip ofsemiconductor material.

Naturally, in order to satisfy local and specific requirements, a personskilled in the art may apply to the solution described above manymodifications and alterations all of which, however, are included withinthe scope of protection of the invention as defined by the followingclaims.

1-8. (canceled)
 9. A computer program directly loadable into a workingmemory of a computer for performing when the program is run on thecomputer, steps of: providing a plurality of reference models arrangedin a tree starting from a root reference model, associating eachdestination unit with a reference model including configurationinformation specific for the corresponding destination units, whereinthe configuration information includes at least one record indicating atarget status of a corresponding configuration element and wherein thetree provides dependency information indicating logic relations betweenthe configuration elements, the target configuration being determinedfurther according to the dependency information of the correspondingconfiguration elements, determining a target configuration for thedestination units associated with a selected reference model accordingto the configuration information of the reference models in a path fromthe root reference model to the selected reference model, causing eachdestination unit associated with the selected reference model to beupdated according to the target configuration, providing an inventorystoring an indication of a current configuration of each destinationunit, and determining a list of actions for reaching the targetconfiguration on each destination unit associated with the selectedreference model according to a comparison between the targetconfiguration and the corresponding current configuration, wherein theconfiguration information includes an indication of at least onedigitally encoded software application product to be installed orremoved and wherein the data processing system comprises a network witha server workstation and a plurality of client workstations each oneassociated with at least one destination unit, the method furtherincluding, for each destination unit associated with the selectedreference model, the steps of building a package under the control ofthe server workstation, the package including each software applicationproduct of the target configuration to be installed and instructions forautomatically executing the list of actions, distributing the package tothe client workstation associated with the destination unit through thenetwork, and updating the inventory according to the actions executed onthe client workstation.
 10. (canceled)
 11. A data processing systemincluding a plurality of destination units, means for providing aplurality of reference models arranged in a tree starting from a rootreference model, means for associating each destination unit with areference model including configuration information specific for thecorresponding destination units, wherein the configuration informationincludes at least one record indicating a target status of acorresponding configuration element and wherein the tree providesdependency information indicating logic relations between theconfiguration elements, the target configuration being determinedfurther according to the dependency information of the correspondingconfiguration elements, means for determining a target configuration forthe destination units associated with a selected reference modelaccording to the configuration information of the reference models in apath form the root reference model to the selected reference model,means for causing each destination unit associated with the selectedreference model to be updated according to the target configuration,means for providing an inventory storing an indication of a currentconfiguration of each destination unit, and means for determining a listof actions for reaching the target configuration on each destinationunit associated with the selected reference model according to acomparison between the target configuration and the correspondingcurrent configuration, wherein the configuration information includes anindication of at least one digitally encoded software applicationproduct to be installed or removed, and wherein the data processingsystem comprises a network with a server workstation and a plurality ofclient workstations each one associated with at least one destinationunit, the system further including, for each destination unit associatedwith the selected reference model, means for building a package underthe control of the server workstation, the package including eachsoftware application product of the target configuration to be installedand instructions for automatically executing the list of actions, meansfor distributing the package to the client workstation associated withthe destination unit through the network, and means for updating theinventory according to the actions executed on the client workstation.12. The data processing system according to claim 11, wherein the meansfor determining the target configuration includes: means for verifying,for each current record of the reference models along the path, if thetarget configuration includes a previous record for the configurationelement of the current record, and means for adding the current recordto the target configuration if the verification is negative or replacingthe target status of the previous record with the target status of thecurrent record if the verification is positive.
 13. (canceled)
 14. Thedata processing system according to claim 11, wherein the configurationinformation includes an indication of at least one hardwarepre-requisite required by the at least one digitally encoded softwareapplication product, the data processing system further including meansfor verifying whether a current hardware structure of each destinationunit associated with the selected reference model meets each hardwarepre-requisite of the target configuration.
 15. The data processingsystem according to claim 11, further including means for running aquery on a memory structure for dynamically extracting a list of thedestination units associated with the selected reference model.
 16. Thedata processing system according to claim 15, further including meansfor excluding each destination unit from the list if a correspondingexclusion flag in the memory structure is asserted, wherein theexclusion flag is associated with a given destination unit.